Chamberlain made 25 throws in a batting cage at the Yankees' minor league complex. He had been throwing off a half-height mound to help regain his form.
"It felt good," Chamberlain said. "Another step forward. That's all you can do."
Chamberlain, who dislocated his right ankle bouncing on a trampoline with his son March 22, has also resumed running sprints in the outfield.
The 6-foot-2, 240-pound right-hander was working his way back from elbow ligament-replacement surgery when sidelined by the ankle injury.
Chamberlain say he will pitch this season.
"Is that even a question?" he said.
David Aardsma threw 40 pitches during his third batting practice session and might be ready to pitch in a simulated game late next week. Aardsma, 13-15 with a 4.20 ERA in 254 relief appearances over six seasons, had elbow-ligament replacement surgery last July.